Cycloaddition and C-H Activation Reactions of a Tantalum Alkylidyne uri icon

abstract

  • 2015 American Chemical Society. The alkylidyne complex (C5Me5)Ta(CPh)-(PMe3)2Cl (1) was first reported by Schrock in 1978, but little if any follow-up work on 1 or other group 5 metal alkylidynes has been reported. This work discloses two avenues of reactivity of 1. Treatment of 1 with 3-hexyne resulted in the formation of a tantalacyclobutadiene. Abstraction of chloride from 1 led to a mixture of products that included isomers of [(C5Me5)Ta(=CHPh)(CH2PMe2)(PMe3)]+ (4), in which a C-H bond of a PMe3 ligand was added across the TaiC bond. The C-H activation was found to be reversible, and the equilibrium mixture functioned as an equivalent of a cationic Ta alkylidyne in reaction with 3-hexyne, producing a cationic tantalacyclobutadiene (6). Compounds 4 and 6 were structurally characterized in the solid state by XRD methods, with 6 being the first structurally characterized metallacyclobutadiene in group 5. (Chemical Equation Presented).

published proceedings

  • ORGANOMETALLICS

altmetric score

  • 0.25

author list (cited authors)

  • Ramirez-Contreras, R., Bhuvanesh, N., & Ozerov, O. V.

citation count

  • 20

complete list of authors

  • Ramirez-Contreras, Rodrigo||Bhuvanesh, Nattamai||Ozerov, Oleg V

publication date

  • January 2015